In many high-end large-area lighting applications, such as those utilising Philips ArenaVision products for example, a large number of luminaires are distributed around an area to be illuminated in an attempt to create a uniform light intensity across said given area. Examples of such applications include arena lighting systems for illuminating sports arenas, e.g. field, pitch or stadium lighting, façade lighting, shop floor lighting, parking lot lighting and so on.
A football stadium, for example, may have a lighting plan or design where the lighting system contains more than 100 luminaires each located on the stadium and with a desired aiming location or point on the pitch to attempt to provide a suitable lighting effect. Typically the lighting system installer receives a light plan which contains, for each luminaire, information such as the type of luminaire, the mounting location and orientation of the luminaire, and the aiming location or point (typically relative to the centre of the field). Based on this information the installer mounts the luminaires in the stadium infrastructure. In this phase, the installer also has to direct the luminaire at the desired aiming location in the field using the lighting plan orientation values.
From the luminaire location, the installer has a clear overview of the field but it is very difficult to accurately determine the aiming location in the field. To improve the accuracy of the alignment procedure, the installer can use a grid created by manually putting visual markers on the field at the required coordinates and a laser pointer aligned with the luminaire optical axis. In such a way the alignment is a matter of aiming the laser spot at the requested visually interpolated locations on the grid. In this procedure the placement of the visual markers on the field is an elaborate task and the alignment itself based on the laser spot is prone to errors.
One way to overcome such difficulties is to pre-aim the luminaires mounted on prefabricated jigs on small scale models of the lighting plan such as discussed within the U.S. Pat. No. 8,717,552. However such systems are unable to adapt to any changes to the building of the stadium. In other words it is difficult or impossible to ‘fine tune’ the luminaires in an effective way. It has furthermore be proposed, such as disclosed in US published application US20130268246 to attach a camera to the luminaire so that the installer is able to ‘see’ where the light from the luminaire will be directed by producing a ‘cropped’ image reflecting the modelled light pattern. This cropped image can then be compared with a further ‘wide-angle’ camera image to determine the location of the light beam and pattern relative to a wide-angle image and so determine whether the luminaire is directed at the required direction.